Back to EveryPatent.com
United States Patent | 6,097,482 |
Smith ,   et al. | August 1, 2000 |
An apparatus for the detection of surface flaws in material having a surface which is partially reflective includes at least one light source arranged to direct incident light on a surface of an at least partially reflective material, and a light detector disposed above the surface of the material. The light detector and the at least one light source are arranged relative to each other such that, in the absence of a surface flaw in the material, substantially no light from the at least one light source is detected by the light detector and, in the presence of a surface flaw in the material, light from the at least one light source is reflected off of the flaw and into the detector.
Inventors: | Smith; Barry Scott (Hopewell, VA); Mullins; Michael J. (Chesterfield, VA); Van Derlinden; Roy E. (Frederick, MD); Irvin; Donald L. (Leesburg, VA) |
Assignee: | Philip Morris Incorporated (New York, NY) |
Appl. No.: | 327531 |
Filed: | June 8, 1999 |
Current U.S. Class: | 356/237.1; 250/237R; 356/237.3; 356/239.1 |
Intern'l Class: | G01N 021/00 |
Field of Search: | 356/237.1,237.2,237.3,237.4,237.5,239.1,239.3,239.7,239.8 250/237 R,227.29 |
3762496 | Oct., 1973 | Milberger et al. | |
3779843 | Dec., 1973 | Knapp. | |
3780570 | Dec., 1973 | Collins. | |
3937065 | Feb., 1976 | Milberger et al. | |
4162126 | Jul., 1979 | Nakagawa et al. | 356/237. |
4377340 | Mar., 1983 | Green et al. | 356/237. |
4509369 | Apr., 1985 | Kuljis et al. | |
4519245 | May., 1985 | Evans. | |
4577337 | Mar., 1986 | Light. | |
4807996 | Feb., 1989 | Ginnis et al. | |
4924182 | May., 1990 | Vernon et al. | |
4936649 | Jun., 1990 | Lymer et al. | |
4939469 | Jul., 1990 | Ludwig et al. | |
4976150 | Dec., 1990 | Deka. | |
5001932 | Mar., 1991 | Light et al. | |
5046363 | Sep., 1991 | Moore. | |
5067352 | Nov., 1991 | Floret. | |
5094108 | Mar., 1992 | Kim et al. | |
5146289 | Sep., 1992 | Newman. | |
5164971 | Nov., 1992 | Peyret et al. | |
5203942 | Apr., 1993 | DeCook et al. | |
5231536 | Jul., 1993 | Wilt et al. | 250/237. |
5265475 | Nov., 1993 | Messinger et al. | |
5289785 | Mar., 1994 | MacPherson et al. | |
5300183 | Apr., 1994 | DeCook. | |
5376793 | Dec., 1994 | Lesniak. | |
5444241 | Aug., 1995 | Del Grande et al. | |
5469294 | Nov., 1995 | Wilt et al. | 250/237. |
5585918 | Dec., 1996 | Takeuchi et al. | 356/237. |
5943127 | Aug., 1999 | Feldman et al. | 356/237. |